welcome to yorkie talk... i'm sorry that you did not find us under better circumstances and that coco is so sick. i'm sorry that i do not have any advice for you, but i will say prayers that they find out what is wrong with your precious coco and that she is all better very soon. hopefully someone with more experience will respond soon.
just to make sure, the chicken and rice that you gave her was plain and did not have any seasoning on it-right? i'm sure it was but just a thought. any kind of spices could irritate her more. also, did coco have any treats / jerky that are made in china before she got sick? we have seen so many pups get sick from them on this site. the fda has issued several warnings to pet owners but the treats are still being sold in the stores because they're still under investigation. there are about 15 brands in question including waggin' train, canyon creek ranch, and milo's kitchen. more info on that can be read by clicking these links
More on Chicken Jerky Pet Treat Alert FDA Continues to Caution Dog Owners About Chicken Jerky Products
again, just a thought. i've been through similar situations with 2 yorkies and both times, in our case, it was pancreatitis but i see that has been ruled out. please know that coco bean will be in my thoughts and prayers. i truly hope she is feeling better today. i know this is so hard on you too financially and emotionally. please keep us updated when you can, i will be checking back to see how she is doing. hugs to you both.